$ git clone -n https://src.fedoraproject.org/rpms/libX11.git /var/lib/mock/f41-build-side-1-2644224-26986/root/chroot_tmpdir/scmroot/libX11
Cloning into '/var/lib/mock/f41-build-side-1-2644224-26986/root/chroot_tmpdir/scmroot/libX11'...
$ git fetch origin ddc5e3368d876332178857fbdd3dce97fe614f9c:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/libX11
 * [new ref]         ddc5e3368d876332178857fbdd3dce97fe614f9c -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at ddc5e33 Fix spurious Xerror when running synchronized